Profit, Loss, and Discount

Core formulas:

Profit = SP - CP
Loss = CP - SP
Profit% = profit / CP * 100
Loss% = loss / CP * 100
Discount = MP - SP
Discount% = discount / MP * 100

Price conversion:

SP = CP * (100 + profit%) / 100
SP = CP * (100 - loss%) / 100
SP = MP * (100 - discount%) / 100

Markup and discount:

If CP = 100,
MP = 100 + markup%
SP = MP * (100 - discount%) / 100
Profit% = SP - 100

Successive discounts:

Net discount = a + b - ab/100

False weight shortcut:

If seller uses x% less weight for same price:
Profit% = x / (100 - x) * 100

Example: 20% less weight => profit = 20/80 * 100 = 25%

Selling two articles:

One sold at x% profit, one at x% loss, same SP:
Net loss% = x^2 / 100

Common traps:

Profit, Loss, and Discount​